1. Field of the Invention
The present invention relates to a liquid crystal display device.
2. Description of the Related Art
A liquid crystal display device has a basic configuration of having polarizing plates on both sides of a liquid crystal cell.
A polarizing plate in a liquid crystal display device has a configuration in which transparent protective films are attached to both front and rear sides of a polarizer made of a polyvinyl alcohol film or the like in which, generally, iodine or a dye is adsorbed and aligned. As the polarizing plate protective film, a cellulose acylate-based polarizing plate protective film represented by cellulose acetate has been widely used due to its favorable transparency and its adhesiveness to a polyvinyl alcohol that is used for a polarizer.
Meanwhile, in recent years, a polyester resin such as PET or a (meth)acrylic resin has become more frequently used as the polarizing plate protective film. This is because an adhesion technique has improved, and it has become possible to ensure adhesiveness to a polyvinyl alcohol.
In recent years, in response to an increase in use of a liquid crystal display device, there has been a demand for a liquid crystal display device with a large size and a high-quality texture. In order to reduce the weight of a large-sized liquid crystal display device, the thicknesses of a variety of members have been decreased and, among them, the thickness of a glass substrate has been decreased from 0.7 mm, the thickness in the related art, to 0.5 mm or lower. Furthermore, in recent years, studies have been underway regarding a glass substrate with a thickness of 0.3 mm.
In JP2012-137723A, studies are conducted regarding color unevenness or color fading occurring when a polarizing plate is placed in a high-temperature environment, and it is found that, when the amount of moisture absorbed is adjusted to be in a certain range when a humidification treatment is carried out on a front-side polarizing plate located on the viewer side of a liquid crystal cell and a rear polarizer located on a side opposite to the front-side polarizing plate respectively, it is possible to control the warping of a liquid crystal panel which has been located in a hot and humid environment when a backlight is turned on, and such an adjustment is effective in improving display unevenness. In addition, it is also found that, when the moisture evaporation rates are respectively adjusted to be in a certain range in the front-side polarizing plate located on the viewer side of the liquid crystal cell and the rear polarizer located on the side opposite to the front-side polarizing plate, it is possible to control the warping of the liquid crystal panel which has been located in a hot and humid environment when the backlight is turned on, and such an adjustment is effective in improving display unevenness.